A rotating electric machine generates heat with operation, and influences characteristics of a permanent magnet provided in the rotor. Therefore, it is necessary to cool the rotor.
JP 2014-176235 A discloses a rotor of a rotating electric machine that includes: a rotor shaft having a refrigerant passage extending in an axial direction and a refrigerant supplying port extending in a radial direction; and a rotor core having a first refrigerant passage extending in the axial direction and a second refrigerant passage facing the refrigerant supply port of the rotor shaft.
As technology related to the present disclosure, JP 2015-104176 A describes a rotor of a rotating electric machine that includes: a rotor shaft having a key groove on the outer periphery side; and a rotor core having a central hole into which the rotor shaft is inserted and a key part that projects further radially inward from the central hole and that is fitted into the key groove. Here, it is described that the key part has a notch along the radial direction and can thereby relax the stress concentration that can be generated at the base of the key part.